Montagna Maria Teresa, Cristina Maria Luisa, De Giglio Osvalda, Spagnolo Anna Maria, Napoli Christian, Cannova Lucia, Deriu Maria Grazia, Delia Santi Antonino, Giuliano Ada, Guida Marco, Laganà Pasqualina, Liguori Giorgio, Mura Ida, Pennino Francesca, Rossini Angelo, Tardivo Stefano, Torre Ida, Torregrossa Maria Valeria, Villafrate Maria Rosaria, Albertini Roberto, Pasquarella Cesira
Department of Biomedical Science and Human Oncology - Hygiene Section, University of Bari, Bari, Italy.
Department of Health Sciences, University of Genoa, Genoa, Italy.
Environ Res. 2016 Apr;146:47-50. doi: 10.1016/j.envres.2015.12.015. Epub 2015 Dec 21.
Legionella is an intracellular microorganism living in natural and artificial aquatic environments. Although its transmission to humans is linked to the inhalation of contaminated aerosols, there is no validated air sampling method for the control and prevention of the disease. The aim of the present study was to provide more information on the distribution of Legionella spp. in indoor environments and to determine whether the same Legionella strains are isolated from air and water samples.
Ten healthcare facilities located in seven regions of Italy were enrolled. The serological typing of Legionella spp. from water samples and the surrounding air by active and passive sampling was assessed using polyvalent and monovalent antisera. Subsequently, the strains identified as Legionella pneumophila (Lpn) underwent molecular typing by sequence-based typing (SBT) using seven genes (flaA, pilE, asd, mip, mompS, proA, and neuA). The allelic profile number was assigned using the European Working Group for Legionella Infections-SBT database.
Lpn serogroup 6 was the most prevalent serogroup; it was found simultaneously in the air and water samples of three different healthcare facilities. In the remaining seven hospitals, Lpn serogroups 1, 6, 7, 9, and 12 were isolated exclusively from water samples. The molecular investigation showed that Lpn strains in the water and air samples of each positive healthcare facility had the same allelic profile. Strains, identified as sequence types (STs) 728 and ST 1638+ST 1324, were isolated in two respective healthcare facilities, and a new strain, identified as ST 1989, was obtained in one healthcare facility.
The application of the SBT method allowed to verify the homology among Legionella strains from water samples and the surrounding air. The results showed that the same Lpn strains were present in the air and water samples, and a new Legionella strain was identified.
军团菌是一种存在于自然和人工水生环境中的细胞内微生物。尽管其传播给人类与吸入受污染的气溶胶有关，但尚无用于控制和预防该疾病的经过验证的空气采样方法。本研究的目的是提供更多关于军团菌属在室内环境中分布的信息，并确定是否能从空气和水样中分离出相同的军团菌菌株。
纳入了位于意大利七个地区的十家医疗机构。使用多价和单价抗血清评估通过主动和被动采样从水样及周围空气中分离的军团菌属的血清学分型。随后，对鉴定为嗜肺军团菌（Lpn）的菌株使用七个基因（flaA、pilE、asd、mip、mompS、proA和neuA）通过基于序列的分型（SBT）进行分子分型。使用欧洲军团菌感染工作组-SBT数据库指定等位基因谱编号。
Lpn血清型6是最常见的血清型；在三个不同医疗机构的空气和水样中同时发现。在其余七家医院中，Lpn血清型1、6、7、9和12仅从水样中分离得到。分子研究表明，每个阳性医疗机构的水和空气样本中的Lpn菌株具有相同的等位基因谱。分别在两家医疗机构中分离出鉴定为序列型（STs）728和ST 1638 + ST 1324的菌株，在一家医疗机构中获得了鉴定为ST 1989的新菌株。
SBT方法的应用能够验证水样及周围空气中军团菌菌株之间的同源性。结果表明，空气和水样中存在相同的Lpn菌株，并鉴定出一种新的军团菌菌株。
